In the design of radio or audio systems for automotive vehicles, performance is optimized by selecting speaker characteristics, speaker placement, filters for cross-over control and other custom hardware for each type of vehicle. Variations in vehicles of a similar type such as the presence of a sun roof or leather seats affects the acoustical properties of the vehicle and the system must be altered accordingly if optimum sound is to be attained. Given that there are different levels of systems from a basic 4 speaker system to an 18 speaker system, even more equipment variables have to be entertained. This poses an expensive design effort for each type of vehicle and further requires an inventory of parts especially selected or made for various types of vehicles.
The basic unit of a vehicle audio system is a radio augmented by other program sources such as a cassette tape player and/or a compact disc (CD) changer or player which are processed by a portion of the radio circuits. With the use of digital technology in sound systems, a digital signal processor (DSP) in the radio processes the incoming audio signal to achieve bass and treble control and room effect simulations, and outputs audio signals to the speakers which are distributed throughout the vehicle.
It is here proposed to use the DSP technology to reduce the proliferation of parts and further to simplify vehicle assembly through the use of common wiring and reduced part numbers, improved heat management, optimized audio performance, and system upgradability.